Rollover safety structure for articulated loaders

ABSTRACT

In an articulated loader vehicle having a rear frame carrying the engine and operator&#39;&#39;s station and having a front frame with spaced upright towers supporting lift arms and a bucket and having means for pivoting one frame relative to the other for steering purposes, rollover protection for the operator is provided by a post extending upwardly from each loader tower to a rectangular top member which is cantilevered back over the operator&#39;&#39;s station. This disposition of the rollover structure on the front frame towers maximizes strength without interfering with other loader components and avoids interference with the operator&#39;&#39;s view of the direction of travel of the vehicle and the bucket during turning.

nited States Patent- Clayton J. T012 [72] Inventor Geneva, Ill. [21]App]. No. 27,902 [22] Filed Apr. 13, 1970 [45] Patented Aug. 17.1971[73] Armigncc Caterpillar Tractor Co.

' Peoria, Ill.

[54] I ROLLOVER SAFETY STRUCTURE FOR ARTICULATED LOADERS V 6 Claims,3Drawing Figs.

[52] 0.8. Cl. 214/140, 280/ 1 50 C [51] Int. Cl. B66f9/00 [50] Field ofSearch 214/140, 131; 280/150 C; 296/102 [56] References Cited UNITEDSTATES PATENTS G QlZ Ph::::;':;:: ::-:":"1 X i.

3,443,833 5/1969 Milleretal.

ABSTRACT: In an articulated loader vehicle having a rear frame carryingthe engine and operators station and having a front frame with spacedupright towers supporting lift arms and a bucket and having means forpivoting one frame relative to the other for steering purposes, rolloverprotection for the operator is provided by a post extending upwardlyfrom each loader tower to a rectangular top member which is cantileveredback over the operators station. This disposition of the rolloverstructure on the front frame towers maximizes strength withoutinterfering with other loader components and avoids interference withthe operators view of the direction of travel of the vehicle and thebucket during turning.

Pmm'wn mm mm 3,599,813

SHEET 2 OF 3 INVENTOR CLAYTQN J TOTZ ATTOEYS PATENTEDAUGITIH?! 3.599.813

SHEET 3 BF 3 INVENTOR C LAYTON J TOTZ ATTORNEYS This invention relatesto articulated loader vehicles and the like and more particularly torollover protective structure for safeguarding an operator in the eventsuch a vehicle overturns.

It is widely recognized that powered vehicles whichiare operated undercertain potentially hazardous conditions should be provided withprotective structure which extends over the operator and is ofsufficient strength to support the weight of the vehicle in theevent thevehicle overturns. This cannot be readily accomplished on certainvehicles without major modifications or interference with the operationof other components. If the protective structure interferes with theoperators view of the worksite or, the path of travel of the vehicle,the structure may itself introduce safety hazards.

Articulated loaders are a class of vehicle in which the above discussedproblems are encountered. Such loaders have from and rear frames eachriding on a single pair of wheels and joined by means which provides forpivoting of one frame relative to the other about a vertical axis forsteering purposes. In many loader designs, both the engine and theoperators compartment are situated on the back frame while a pair ofupwardly extending spaced-apart towers on the front frame support liftarms which carry the loader bucket.

In providing rollover protection for these loaders it has heretoforebeen the practice to secure the protective structural members to therear frame. Difficulties and complications have resulted in that manyloader designs do not offer anchoring points in the vicinity of theoperator's station which are of sufficient structural strength to assuresafety and which can be utilized without interfering with othercomponents of the vehicle. To provide adequate support, it has beennecessary to use undesirably complex protective members or to extendsuch members to points on the rear frame which are remote from theoperators station. If the protective members extend towards the front ofthe operators station, a further difficulty is encountered. Inparticular, articulation of the loader in the course of turning causesthe forward frame to pivot away from a longitudinal axis through therear frame. At this time, forwardly situated protective members maypartially obscure the operators view of the direction of travel of thevehicle and of the bucket. This is highly undesirable both from thesafety standpoint and with respect to working efficiency.

SUMMARY OF THE INVENTION This invention is a compact, high strengthrollover protective structure for articulated loader vehicles which isadaptable to most loader designs and which maintains the operatorsnormal view of the loader bucket and the direction of travel of thevehicle during turning. Rollover protective members are secured to thefront frame of the loader and the top of the structure is cantileveredback over the operator's station on the rear frame. In particular, theprotective structure is anchored to high strength elements of the frontframe which were designed to sustain the heavy load forces on thebucket. The protective structure turns with the front frame duringturning of the vehicle and thus does not interfere with the operatorsview of the line of travel at such times.

Accordingly, it is an object of this invention to provide compact, highstrength rollover protection means for the operator of an articulatedloader which is-adaptable to a variety of loader designs and which doesnot impair visibility of critical areas during turning.

The invention, together with further objects and advantages thereof,will best be understood by reference to the following description of apreferred embodiment in conjunction with the accompanying drawings.

- fBRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings: I

FIG. 1 is a side elevation view of an articulated loader vehicle havingrollover safety structure in accordance with the invention,

FIG. 2 is a front elevation view of the loader of FIG. 1, and

FIG. 3-isa plan view of the loader vehicle of FIG. 1 with the frontframepivoted relative to the rear frame to turn thevehicle.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2 ofthe drawings in conjunction, an articulated loader ll'typical of thetype to which the invention is applicable has a front frame 12 riding ona single pair of front wheels 13 and a rear frame 14 riding on anadditional pair of wheels 16. The driving engine 17 is carried on theback portion of rear frame 14 while front frame 12 includes a pair ofhigh strength loader towers 18 which extend upwardly at each side of thevehicle A pair of lift arms 19 extend forward from the upper end oftowers 18 at each side of the vehicle to support the bucket 21. The backends of arms 19 are coupled to the towers 18 through pivot axles 22whereby the arms may be raised and loweredlto manipulate bucket 21 inthe manner known to the art. Bucket 21 is coupled to the forward end ofthe lift arms 19 at pivot joints 23 and conventional tilt linkage 24 isconnected between the bucket and lift arms to maintain the bucket in asubstantially constant inclination as the arms are raised and lowered.The tilt linkage includes hydraulic tilt jacks 26 for selectivelychanging the attitude of the bucket 21, suitable detailed structure forsuch mechanism being known in the art.

The front and rear frames 12 and 14 respectively are coupled together bya kingpin hitch 27 which provides for pivoting of one frame relative tothe other about a vertical axis, by means of steering jacks .28, for thepurpose of steering the vehicle. The operators station 29 may include aclosed cab 31 and is situated on the upper forward portion of the rearframe 14 preferably at the pivot axis of hitch 27. This position of theoperators station 29 allows the operator to view the bucket 21 and thearea immediately ahead of the vehicle.

Considering the rollover safety structure 32 for safeguarding theoperator in the event the loader should overturn, a post member 33extends upwardly and slightly rearwardly from each loader tower 18 ofthe front frame 12. Post members 33 are of sufficient strength tosupport the weight of the loader vehicle 1 l and are attached to theupper ends of loader towers 18 by high strength fastening means such asbolts 34. The

pivot axles 22 which attach the lift arms to the loader tower areextended through the post members 33 to further strengthen theattachment. The protective structure 32 is completed by a rectangularmember 36 extending between the tops of post members 33 and supportedthereby and extending rearwardly above the operators station 29 on backframe 14. In this example of the invention, the rectangular top member36 and posts 33 are fabricated as an integral unit but it will beapparent that essentially the same construction can be assembled fromseparate members attached together by suitable fasteners.

Should the loader l1 overturn in operation, the operator is safeguardedby the rollover safety structure 32. The mounting of the rollover safetystructure 32 on the loader towers 18 of the front frame 12 isparticularly advantageous in that the towers are designed to withstandthe high load forces generated by bucket manipulations and are alsosituated adjacent the front of operators station 29 whereby theprotective structure may be of relatively small bulk and complexity. Asbest illustrated in FIG. 3, the spaced post members 33 define a window35 through which the operator may view the bucket 21 and the directionof travel of the vehicle and this view area is not affected by turningof the vehicle as the posts 33 turn with the front frame 12. If desired,as shown in FIG. 1,

suitable openings 37 may be provided in the posts 33 to minimizeinterference with the operators view of the regions at each side of thebucket and direction of travel.

It will be apparent that variations in the described structure arepossible and is not intended to limit the invention except as defined inthe following claims.

What I claim is:

l. Rollover safety structure for an articulated loader vehicle having arear frame carrying an operators station and a front frame supporting abucket for carrying material wherein said front and rear frames arejoined by means providing for forced relative pivoting therebetweenabout a vertical axis to steer said vehicle, said rollover structurecomprising:

a pair of spaced-apart post members each having a base secured to oneside of said front frame and extending in a substantially upwarddirection therefrom, and

a top member extending between said pair of post members and extendingrearwardly therefrom over said operators station of said rear frame.

2. The combination defined in claim 1 wherein said front frame of saidarticulated loader vehicle has a pair of upwardly extending loader towermembers disposed one at each side of said frame for supporting saidbucket and wherein said bucket is fastened to said front frame by a pairof lift arms coupled to the upper ends of said loader towers by pivotaxles, wherein each of said post members is secured to the upper end ofa separate one of said loader towers.

3. The combination defined in claim 2 wherein said pivot axles whichcouple said lift arms to said loader towers extend through theassociated one of said post members to strengthen the fastening of saidpost members to said loader towers.

4. The combination defined in claim 1 wherein said post members haveopenings therein enabling the operator to view regions forwardly andsidewardly of said bucket through said post members.

5. The combination defined in claim 1 wherein said operators station issituated substantially above said vertical pivot axis between said frontand rear frames and wherein said top member of said rollover protectivestructure extends above said pivot axis whereby said top member remainsabove said operator's station irrespective of angling of said frontframe relative to said back frame.

6. A rollover safety structure for attachment to an articulated loaderwhich has a rear frame supporting an operator's station and a frontframe which may be pivoted relative to the rear frame and which carriesa pair of spaced-apart loader towers for supporting a bucket, comprisinga pair of spacedapart parallel post members each having means at thebase thereof for attachment to a separate one of said loader towers tosupport said safety structure thereon with said post members extendingupwardly from said loader towers when attached thereon, and a top memberextending between said post members and being angled with respectthereto to extend back over said operator's station of said rear framewhen said safety structure is attached to said from frame.

1. Rollover safety structure for an articulated loader vehicle having arear frame carrying an operator''s station and a front frame supportinga bucket for carrying material wherein said front and rear frames arejoined by means providing for forced relative pivoting therebetweenabout a vertical axis to steer said vehicle, said rollover structurecomprising: a pair of spaced-apart post members each having a basesecured to one side of said front frame and extending in a substantiallyupward direction therefrom, and a top member extending between said pairof post members and extending rearwardly therefrom over said operator''sstation of said rear frame.
 2. The combination defined in claim 1wherein said front frame of said articulated loader vehicle has a pairof upwardly extending loader tower members disposed one at each side ofsaid frame for supporting said bucket and wherein said bucket isfastened to said front frame by a pair of lift arms coupled to the upperends of said loader towers by pivot axles, wherein each of said postmembers is secured to the upper end of a separate one of said loadertowers.
 3. The combination defined in claim 2 wherein said pivot axleswhich couple said lift arms to said loader towers extend through theassociated one of said post members to strengthen the fastening of saidpost members to said loader towers.
 4. The combination defined in claim1 wherein said post members have openings therein enabling the operatorto view regions forwardly and sidewardly of said bucket through saidpost members.
 5. The combination defined in claim 1 wherein saidoperator''s station is situated substantially above said vertical pivotaxis between said front and rear frames and wherein said top member ofsaid rollover protective structure extends above said pivot axis wherebysaid top member remains above said operator''s station irrespective ofangling of said front frame relative to said back frame.
 6. A rolloversafety structure for attachment to an articulated loader which has arear frame supporting an operator''s station and a front frame which maybe pivoted relative to the rear frame and which carries a pair ofspaced-apart loader towers for supporting a bucket, comprising a pair ofspaced-apart parallel post members each having means at the base thereoffor attachment to a separate one of said loader towers to support saidsafety structure thereon with said post members extending upwardly fromsaid loader towers when attached thereon, and a top member extendingbetween said post Members and being angled with respect thereto toextend back over said operator''s station of said rear frame when saidsafety structure is attached to said front frame.